GE POL Diamonds: Before and After
This article explores and identifies the changes that type IIa GE POL diamonds experience before and after HPHT annealing.
A History of Diamond Treatments
Modern gemmologists and diamantaires are faced with a broad spectrum of colour and clarity treatments ranging from the simple to the highly sophisticated.
A New Lasering Technique for Diamond
Several diamonds were treated for the purposes of observation and report with a new laser technique which does not show the typical surface-reaching drill hole.
The Characteristics and Identification of Filled Diamonds
This article reports on the study of six diamonds, both before and after a filling treatment, and the examination of 12 additional filled stones.
Treated-Colour Pink-To-Red Diamonds from Lucent Diamonds Inc.
Using a multi-step process, Lucent Diamonds has developed a new treatment process for certain natural diamonds that creates colours from pink-purple to red to orangey brown.
Synthetic Moissanite: A New Diamond Substitute
Synthetic moissanite is much closer to diamond in overall appearance and heft than any previous diamond imitation; this article reports on how to identify and characterise it.
A Chart for the Separation of Natural and Synthetic Diamonds
Exploration of a chart designed to give jewellers and gemmologists a practical guide to identifying synthetic diamonds as they enter the jewellery trade.
An Update on Filled Diamonds: Identification and Durability
This report focuses on recent products from Yehuda/Diascience, Koss & Schecter Diamonds (Genesis II) and Clarity Enhanced Diamond House (a subsidiary of Goldman Oved Diamond Co.).
Cutting Diffraction Gratings to Improve Dispersion (“Fire”) in Diamonds
A new microlithography process developed to create high-resolution diffraction grating patterns on portions of certain facets can improve the dispersion of light and thus the amount of “fire” in a diamond.
The “Type” Classification System of Diamonds and Its Importance in Gemmology
Knowledge of type allows gemmologists to better evaluate if a diamond might be treated or synthetic, and whether it should be sent to a laboratory for testing.